Determination of Fluorine Using Electrothermal Vaporization Coupled to Inductively Coupled Plasma Optical Emission Spectrometry
Fluorine (F) can be found in many consumer products because of its diverse beneficial properties and high efficacy as a functional group or additive. With excessive chronic exposure, it can yield negative effects on an organism and thus must be monitored carefully. Due to its high ionization potential, F is considered as a difficult analyte to monitor and improvements for its detection are of interest. The work conducted in this thesis explored solid sampling electrothermal vaporization (ETV) coupled to inductively coupled plasma optical emission spectrometry (ICPOES) for the determination of F in plant-based materials. A method was developed for ETV-ICPOES to determine F in solid samples, where atomic emission of F was monitored. This technique eliminated time-consuming sample preparation procedures, like acid digestion, which would typically precede analysis for traditional methods. To extend the capability of ETV-ICPOES for F detection, standard solutions were explored for external calibration to eliminate the need for matrix-matched reference materials. This method allowed quick screening of F in both solid samples and standard solutions using ETV-ICPOES. To improve the detection of F using ETV-ICPOES, an Ar-H2 mixed-gas ICP was investigated, where H2 was mixed with the Ar carrier gas through the ETV furnace. Comparing the method with and without H2, the addition of H2 degraded the sensitivity of F in solid samples. Despite a degradation in sensitivity, the detection limits were improved in solid samples, allowing more accurate detection of F with a mixed gas ICP. This method was not applicable to standard solutions, as it degraded both sensitivity and detection limits following H2 addition. Utilizing ETV-ICPOES, methods for the detection of F were investigated and developed, allowing for rapid determination in a variety of solid and liquid samples.